A need exists for lightweight intake manifolds for internal combustion engines capable of withstanding significant internal pressures. Many prior art intake manifolds have been fashioned from cast aluminum which, for a typical four cylinder internal combustion engine, may weigh approximately 15 pounds and may act to heat the intake air charge, adversely affecting performance. Moreover, there is a need for internal combustion engine intake manifolds having internal passages shaped and sized for efficient air flow. What is needed is a lightweight, high strength, low thermal mass intake manifold having internal passage geometry adapted to facilitate air flow and a method for making such an intake manifold.